invention relates to a mobile sign with a solar panel, and in particular to a mobile sign wherein the solar panel is tiltable and rotatable relative to the trailer on which the sign panel is mounted. Another aspect of the present invention is a low-glare, high-contrast display.
Highway warning signs are frequently needed to warn motorists of obstructions, traffic delays, and hazardous conditions as such conditions arise. To be most useful, a highway warning sign should be mobile so that the sign may be transported to the site of the obstruction. Once the sign has been moved to the site of the obstruction, the sign may be left along the highway to warn passing motorists.
In order to be visible in a variety of lighting conditions (bright sunlight, overcast, nighttime, etc.) the sign's warning should be illuminated, i.e., the sign elements should be electrically powered. The sign elements may be light emitting diodes (LEDs) or dot sign units which flip over and are alternately illuminated when flipped over in order to spell out a message on the sign.
Because electrical power may not be available at the site of the hazard or obstruction, the sign should operate off batteries. However, the batteries should also be rechargeable from solar energy because of the limited charge lifetime of any battery. Therefore, the sign should have a solar panel for recharging the batteries.
There is a need for a mobile sign with a solar panel which can be adjusted to the position of the sun without moving the trailer, in order to maximize the ability of the solar panel to charge the batteries.
A mobile highway sign must also have a display that is highly visible under a variety of lighting conditions. Reflected glare from the sun should be minimized while the contrast of the sign's display should be maximized. There is a need for a mobile sign with a display that minimizes reflected glare and at the same time maximizes the contrast of the display.
Heat from the sun may reduce the life of electronic components of the sign and of display elements such as light-emitting diodes (LED). There is a need for a sign with a display which reduces the amount of heat from the sun entering the display.